Eyes in the Sky: What You Should Know About Satellites

Satellites are a common technology nowadays. Yet every launch costs million of dollars and involves a lot of risks. If one single thing goes wrong, those millions of dollars and hundreds of hours invested are gone.

However, satellites do provide invaluable information that could only be vaguely estimated from the ground. With sophisticated sensors and by repeating their orbit around the Earth over and over again, they can monitor the tiniest variations in the Earth atmosphere.

In the last few years, satellites have been put to use for the following purposes:

The Global Positioning System (GPS) used in your car can also be used to detect tiny movements in the Earth’s crust as slow as millimeters per year. Cracks and strain patterns can be identified, helping to forecast the next seismic disaster and potentially saving thousands of lives.

The GOCE satellite (Gravity field and Ocean Circulation Explorer) has allowed scientists to measure and map gravity across the planet. This information was only estimated until the satellite was put into use in 2009. It can be used to further understand oceanic activity and help predict earthquakes. Regrettably, this satellite has been destroyed.

The Soil Moisture and Ocean Salinity satellite, known as SMOS, helps us understand the varying levels of salinity in oceans and of moisture in soil. It contributes to better weather forecasting, to the study of ice and snow accumulation and to better understanding of climate.
Infrared imaging has revealed pyramids buried under Egyptian sand for millennia that had remained unknown to man. More than 1000 tombs and 3000 settlements were found in 2011.

Satellite-based LIDAR (Light Detection and Ranging) is similar to RADAR, which uses radio waves, in that it uses laser rays to calculate distance. It is used to study everything from weather patterns to the rainforest canopy.CryoSat-2, launched in 2010, measures the thickness of the polar ice caps with a resolution of half an inch. It provides vital information on climate change, ocean circulation and sea-level rises.

GPS is applied to biological and earth sciences in many different ways like tracking bird migrations or monitoring changes in the topography of Antarctic ice.

Satellites can also monitor the amount of carbon dioxide and methane emitted and absorbed by the Earth, helping us understand the carbon cycle, greenhouse gases and humans’ contributions to their emission.

These satellites are extremely relevant to our environmental situation right now. Perhaps the days of space exploration are over, and priority should be given to launching satellites that can help us better understand our own planet. Through satellite studies, we can hope to fully comprehend all the different systems that play a role in climate change and seismic activity.